Fratricide, or the inadvertent killing of friendly forces by other friendly forces, has been a persistent concern, probably since the inception of warfare. Even with the advancement of smart weapons, fratricide by indirect fire projectiles after the munition is fired, has not been eliminated. A conventional solution to fratricide has been the use of an identification, friend or foe (IFF) system.
In general, an IFF system is an identification system that enables a military interrogation system to identify a friendly force and to determine whether a potential target should be engaged. Although the IFF system has proven to be helpful, there still remains a need for an anti-fratricide responsive ordnance system that disarms the munition, particularly during flight, after it is has been fired.
Numerous IFF systems, reconnaissance systems, and safety and arming devices have been proposed, among which are those described in the following publications: Prestwood, U.S. Pat. No. 3,298,023; Hulland, et al., U.S. Pat. No. 4,642,648; Joguet, U.S. Pat. No. 5,001,488; Jelinek, U.S. Pat. No. 5,327,145; Hulderman, et al., U.S. Pat. No. 6,025,795; Galli, U.S. Pat. No. 7,295,296; Arevalo, et al., U.S. Pat. No. 8,176,834; Lucas, et al., (U.S. Patent Application No. 2006/0042494); and Ivtsenkov, et al., U.S. Patent Application No. 2010/0289691.
However, many of these systems propose pre-fire IFF, line-of-sight, interrogation-based approaches to identify whether a potential target is a friend or a foe.
Therefore, a need arises for a post-fire IFF, non-line-of-sight, non-interrogation-based system that disarms an approaching munition when it enters a kill radius of the friendly force, and which is capable of re-arming the munition upon exiting the kill radius. The need for such an anti-fratricide system has heretofore remained unsatisfied.